This study is concerned with the role of human papillomaviruses in the etiology of cancer. The individual projects will address the epidemiology of these virus infections and the mechanisms through which neoplastic transformation of host cells is mediated. Case-control studies will evaluate the hypothesis that infection with HPV is related to an increased risk of cancer and that other factors may contribute to an initiator/promoter mechanism. Biochemical and serological support for the epidemiological studies will be utilized and developed in the research program, the methods for which include molecular hybridization in situ and with nitrocellulose blotting, immunoperoxidase staining, antibody evaluation and molecular cloning in expression vectors to provide defined viral antigens and antibodies.